Heat exchanger



United States Patent 3,380,517 FOREIGN PATENTS 842 5/1924 Great MiltonMenkus [72] Inventor ry phil W. Streule 064,137 12/1953 France PrimaryExaminer-Robert A. OLea Arm-rant Examiner-Theo [22] Filed July8,1969[45] Patented Dec. 22, 1970 Continuation-impart of application Ser. No.612,927,, Jan. 31, 1967, now Patent No, Attorneys-Kenwood Ross andChester E. Flavin 3,470,950, dated Oct. 7, 1969.

Fzab 3/02 checkerboard fashion with portions of certain of the barriers165/165' d for defining ports and permitting intercommunicaong separatetortuous acent interconnectin [51] Int." [50] Flcldofsearcll........

ach end of the stack acting to mutually perpendicular inlet flows ofcertain w courses and outlet flows of certain other of the flow remove166 tion between certain chambers and a1 flow courses between series ofad {561 References CM chambers, and headering means at e UNITED STATESPATENTS commoda Jones............................ 165/166 of the fluSoutham 16511661 courses FIGJ.

INVENTOR. MILTO NKUS ATTORNEYS.

FATENIEUnEczemm 3548.932

SHEET 2 (IF A ATTORNEYS.

PATENTEU BEC22 ism FIG.3.

INVENT MILTON ME s ATTORNEYS.

PATENTEUUEI322|97U 3548832 SHEET t 0F 4 TEMPERED OUTSIDE AIR TO AIRHANDLING UNIT OUTSIDE CONTAMINATED AIR TO BE ROOM AIR HEATED COOLED AIRTo EXHAUST FAN INVENTOR.

MILTON M ENKUS BY @014 e ATTORNEYS.

HEAT EXCHANGER CROSS REFERENCES TO RELATED APPLICATION BACKGROUND OF THEINVENTION 1 Field of the Invention The invention relates to alabyrinth-type heat exchanger for effecting the transfer of heat from aplurality of flows of one fluid, each flowing a adjacent one side of aplurality of barriers, to a plurality of flows of another fluid, eachflowing adjacent the other side of the plurality of barriers, withcooperant headering means at each end of the exchanger, each headeringmeans allowing the conduct of the one fluid from the plurality of flowsthereof to and through the headering means at one end thereof to a firstcooperating duct and the conduct of the other fluid from the pluralityof flows thereof to and through the headering means at right angles ofthe first named one end to a second cooperating duct.

2. Description of the Prior Art Efficient heat exchangers of the priorart have been expensive in manufacture, complicated in design, lackingin flexibility as to fields of use, and limited as to scope ofapplication.

The need for an efficient heat exchanger of simple construction, yetwith a high rate of heat transfer, together with a facility, by virtueof a manifolding feature, to provide a wide range of capacities, haslong been felt. Y

Simple headering means at each end of the structure to handle aplurality of fluid flows, traveling in the same or opposite directions,has long been needed. In the case of a labyrinthtype heat exchanger,where a plurality of side-by-side fluid passageways discharge into acommon header at one end of the structure, with certain thereof being.ingoing in flow direction and others thereof being outcoming in flowdirection, the side-by-side alternating arrangement presents outrageousproblems of design in the matter of headering all of the ingoingpassageways to a common duct without interfering with the headering ofall of the outgoing passageways to another common duct.

SUMMARY OF THE INVENTION The invention provides a heat exchanger ofmodular design,

- used as either a parallel 'or counterflow type, wherewith infinitevariations can be'approached by the's imple expedient of increasing ordecreasing the number of modules or elements, or the size of themodules, or the length or configuration of the flow paths.

The heat exchanger accommodates fluids having an extremely high rate ofheat transfer resultant from the unique provisions for the fluid flowpaths through the structure.

The headering means is so arranged that the directions of the inlet andoutlet fluid flows into and from the elements at each end thereof aremutually perpendicular.

The heat exchanger has as many applications as there are uses for heatexchangers generally. For example, it may serve as a boiler or anappendage thereto, as a furnace, as a roof or wall or other structuralpanel of a building or room or the like with inherent ducting and heatexchange capabilities, or as a separate accessory where outside air usedfor make-up in a building or room may be heated by air being exhaustedtherefrom. Further, it may be exploited by its use for acousticaltreatments inherent in its design as a labrinth-type heat exchanger,same lending themselves to instances where noise is a serious problem inconnection with air or other fluid handling. a

The invention offers the advantage of being economically producible soas to allow ready removal and replacement with an almost completeelimination of maintenance costs, all based upon the principle ofplanned replacement.

The invention broadly comprehends acceleration and deceleration of fluidflow due to variations in the area available in the course ofintercellular flow as fluid is progressed through a flow path andpulsing-type velocity changes in fluid .flow resulting in expansion orcontraction, causing the labyrinth or helical flow to accelerate anddecelerate and to change paths whereby turbulence is increased so as toenhance heat transfer.

BRIEF DESCRIPTION OF TI-IE'DRAWINGS FIG. I is a fragmentary view, inperspective, of the heat exchanger made up of a plurality of heattransfer cellular elements in a cooperating stacked relationship;

FIG. 2 is a view, in top plan, of the topmost heat transfer cellularelement of FIG. 1, with the upper wall or plate removed;

FIG. 3 is an enlarged fragmentary view, in top plan, of one of the heattransfer cellular elements;

FIG. 14 is a small scale schematic view of a typical heating applicationillustrating the general direction of movement of the fluid flow paths;and

, FIG. 5 is a small scale schematic view of another typical heatingapplication illustrating another general direction of the movement ofthe fluid flow paths.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The term fluid, as hereinemployed, will be understood to mean anything that will flow, whether ofliquid or gaseous form.

The term heat exchanger" has been used for purposes of convenience, andin the classical sense of any device used to transfer heat from a fluidflowing on one side of a barrier to another fluid flowing on the otherside of the barrier.

The heat exchanger may take the form of one or more elements, enclosedand separated by walls or plates, and connected, as by suitable inletheader or inlet lines and associated ducting, to supply sources ofheated and/or cooled fluids and, as by suitable outlet headers or outletlines and associated ducting, to other fluid-handling means.

In FIG. 1, I have shown a heat exchanger or manifold or sandwichconstruction comprising a plurality of intermediate heat transfercellular elements, generally designated l0, disposed between anuppermost heat transfer cellular element 12 and a lowermost heattransfer cellular element Id. The elements are vertically stacked, oneabove another, with each element being separated from adjacent elementsby intermediate walls or plates 16. Uppermost heat transfer cellularelement I2 is also enclosed on its outboard side by an uppermost wall orplate 18 and lowennost heat transfer cellular element 1 4 is alsoenclosed on its outboard side by a lowermost wall or plate 20.

While only five heat transfer cellular elements have been shown in FIG.1, I do not desire to be limited thereto since any number of elements ofany desired flow path length or arrangement may be employed to meetdifferent installation requirements.

The elements are suitably enclosed at their opposite sides by sidewallsor side plates 22 and the opposite ends are suitably connected toheaders for fluid flow inlets and outlets, subsequently to be more fullydescribed.

Each heat transfer cellular element, sometimes called a grille, includesa plurality of equispaced, parallel, upright, longitudinally extendingwalls 32 and a plurality of equispaced, parallel, upright, transverselyextending walls 34 normal to and intersecting the first-named walls, thetwo sets of walls cooperantly defining a plurality of generally squareor other shape cells or chambers 36.

The opposite intermediate or uppermost or lowermost walls or plates 16,I 8, 20 respectively, as the case may be, may be defined ascell-enclosing walls and are each mutually perpendicular to both thelongitudinally and transversely extending walls, 32, 34 respectively.

40, 42 respectively spaced along their lengths, which ports extenddownwardly from the upper planar edges of the walls 32, 34 and areequispaced in manner to afford communication between certain of theadjacent cells 36 along zigzag or tortuous or sinuous courses.

In the case of each heat transfer cellular element, the socalledcell-enclosing walls and certain of the ported portions and certain ofthe non ported portions of certain of the longitudinally andtransversely extending walls cooperantly define a multiplicity of spacedprimary series of intercommunicating fluid-carrying cells disposed in acommon plane, with each of such primary series defining a tortuous firstfluid-flow path identified by the arrows A (in FIG. I), and amultiplicity of spaced secondary series of intercommunicatingfluid-carrying cells disposed in the same common plane, with each ofsuch secondary series defining a tortuous second fluid-flow pathidentified by the arrows B.

As shown, each secondary series is contiguously juxtaposed between anadjacent pair of the primary series.

The fluid-flow paths indicated by arrows A may be heated paths and thefluid paths indicated by arrows B, may be cooled paths in a counterflowarrangement. The paths can be of the parallel type, if desired,counterflow being herein illustrated wherein paths A and B alternatethroughout the width of each element.

By stacking the elements, greater capacity of fluid flow and morecomplete and efficient heat transfer is obtained. For example, a certainflow path of the topmost intermediate element in FIG. 1 is bounded ontwo of its sides, in its own plane, by adjacent oppositely flowing flowpaths, is bounded on its upper side in the next upper horizontal planeby a flow path of upper element 12, and is bounded on its lower side inthe next lower horizontal plane by a flow path of the next adjacentintermediate element 10.

' Of course, the relationship between the flow paths in each of theseveral planes may be varied. That is, a heated fluid path in one of theintermediate elements may be bounded on its upper and lower sides byheated or cooled fluid paths and it may be bounded on all of its sidesby parallel or counter flow paths.

It is to be noted that, when flow paths are of equal lengths, equalpressure drops are maintained from the inlet header to the outletheader, thereby avoiding short-circuiting paths which tend to reduce theoverall efficiency of heat transfer. Differing flow path lengths may beutilized in those instances where it might be advantageous to do so, asin a triple, quadruple or larger fluid heat exchange system.-

The flow paths here provided offer the advantage of obtaining greaterturbulence of the fluids passed therealong.

As shown in FIG. 2, the heat transfer cellular element is arranged as aparallelogram for ease of headering. Were the element square orrectangular, all of the fluid flow inlets and all of the fluid flowoutlets at one end of the element would be in the same vertical plane soas to aggravate the headering problem.

Since each flow path must have its own inlet at one end and at its ownoutlet at the other-end, the headering space problem can reachtremendous proportions. It is a simple enough problem to interconnectthe multiplicity of staggered inlets in a common plane or tointerconnect the multiplicity of staggered outlets in the same commonplane; it is quite another matter both to interconnect all inlets and tointerconnect all outlets when all are not in a common plane.

My solution to this problem is achieved by disposing the flows of theinlet and outlet headers at right angles to each other at each end of aheat transfer element or a stack thereof.

As best seen in FIG. I, a plurality of enclosed horizontally disposedinlet conduits or connector channels 50 are connected at their inboardends to the outermost end wall 34 of the heat transfer cellular element,one serving every other port 42. These conduits or connector channelsare connected at their opposite outboard ends to a vertically-disposedwall 60 The area between the outermost end walls 34 of the elements ofthe stack and the wall 60 defines a triangular-shape headering areathrough which the spaced inlet conduits extend in a bridging manner andinto which the other ports 42 in the outermost end wall 34, no soconnected to inlet conduits 50, discharge their fluids. These ports may,if desired, be provided with wall extensions 33 on the adjacent walls 32which extend slightly into the headering area so as to cause the fluidflow passing therethrough to turn angularly away from the general axesdefined by the conduits 50.

The outlet fluid flows in the oppositedirection from that of the inletfluid and passes directly through the last of the series of open ports42 between each of the inlet conduits 50 and then flows freely over andunder and around the conduits 50 which are staggered as to each other,to a secondary duct 66, (see FIG. 2).

This arrangement is repeated at each end of the stack of heat exchangeelements as shown in FIG. 2, wherein inlet directions are indicated bythe arrows a and outlet directions are indicated by the arrows b, whichinlet and outlet directions are mutually perpendicular to each other inthe same plane at both ends of the heat exchanger.

As shown, the assembled heat exchanger with its headers is generallyrectangular in plan so that all flow paths are of the same length.

Cell enclosing plates 16, 18 and 20 may be provided with wings orextensions l7, l9 and 21 respectively which may serve as strengtheningribs.

In a typical application, flow of outside air to be heated is into theexchanger via arrow B and outwardly of the exchanger via arrow A astempered outside air to the air handling unit, as illustrated in FIG. 4.Therein, the contaminated room air follows a counterflow pattern viaarrow B through the exchanger and outwardly thereof as cooled air to theexhaust fan via arrow A.

Alternatively, as shown in FIG. 5, theflow via arrow A may be into theexchanger at one end and outwardly thereof via arrow A at the oppositeend, with the counterflow being into and from the exchanger via arrows Bat opposite sides thereof and at right angles to the flow of the fluidsof arrow A.

I claim:

1. In a labyrinth-type heat'exchanger for transferring heat I from hightemperature sources of heat-transferring fluid flow to low temperaturesources of heat-receiving fluid flow and ineludi g a core having top andbottom walls and one end connected to an inboard-headering means and anopposite end connected to an outboard-headering means and comprised by astack of grilles disposed in a multiplicity of parallel planes separatedfrom each other by a cell-enclosing wall and with each grillecomprising:

a. a plurality of cells defining a multiplicity of primary series ofintercommunicating fluid-carrying cells each arranged as a first fluidflow course having a terminal port at each end of the grille and amultiplicity of secondary series of intercommunicating fluidcarryingcells each arranged as a second fluid flow course having a terminal portat each end of the grille; b. with each second fluid flow course beingcontiguously juxtaposed between and in sealed relation with an adjacentpair of first fluid flow courses and with the terminal ports of eachfirst fluid flow course being spaced from the terminal ports of the nextadjacent second fluid flow courses; the improvement in the inboard andoutboard headering means with each headering means being constituted by:A. a primary duct having a wall connected at one side edge thereof toone side edge of the adjacent end of the stack; B. a secondary ductconnected at one side edge thereof to the other side edge of theadjacent end of the stack and interconnected to the other side edge ofthe primary duct wall, the secondary duct being in right angularrelationship with the primary duct;

C. a header enclosed by the interconnected adjacent end of the stack andthe primary and secondary ducts and a header-enclosing wall at thetopand at the bottom of the stack;

D. a plurality of connector channels spaced as to each other in and eachextending through the header and connecting between and communicativelyconnected to one of the terminal ports of the first fluid flow coursesand the wall of the primary duct for allowing fluid flow communicationthrough the connector channels and between the first fluid flow coursesand the primary duct and fluid flow communication between the secondfluid flow courses and the adjacent terminal ports thereof and thesecondary duct by way of sinuous flow within the header and around theexterior walls of the connector channels; and

E with cross-sectional dimensionsof each headering means correspondingto the cross-sectional dimensions of the core.

2. In a labyrinth-type heat exchanger for transferring heat from hightemperature sources of heat-transferring fluid flow to low temperaturesources of heat-receiving fluid flow, the improvement consisting of:

A. a plurality of grilles disposed in stacked relationship in amultiplicity of parallel planes:

a. each grille comprising a plurality of longitudinally extending wallsintersected by a plurality of transversely extending walls defining aplurality of cells;

b. a cell-enclosing wall disposed between and common to pairs ofadjacent grilles of the stack and a cell-enclosing wall disposed on theopposite outer sides of the stack, each cell-enclosing wall beingmutually perpendicular to the longitudinally and transversely extendingwalls; l

c. certain portions of certain of the longitudinally and transverselyextending walls being ported;

d. the cell-enclosing walls and certain of the ported portions andcertain of the nonported portions of certain of the longitudinally andtransversely extending walls cooperantly defining:

1. a multiplicity of spaced primary series of intercommunicating fluidcarrying cells disposed in a common plane with each such series defininga. helically shaped first fluid-flow course; and

2. a multiplicity of spaced secondary series intercommunicatingfluid-carrying cells disposed in the same common plane with each suchseries defining a helically shaped second fluid flow course flowingcounter to the direction of the first fluidflow course;

e. each of the secondary series being contiguously juxtaposed between anadjacent pair of primary series;

f. and each of the secondary series of each intermediate grille beingjuxtaposed adjacent a primary series on each of its sides;

g. with each wall of the secondary series being contiguously juxtaposedin heat transfer relation with a wall of an adjacent primary series; and

B. inboard and outboard-headering means at opposite ends of the stack ofgrilles with the cross-sectional dimensions of each headering meanscorresponding to the cross-sectional dimensions of the stack.

